The influence of subterranean clover pastrues on soil fertility. I. Short-term effects

Abstract

Under a subterranean clover pasture on a light-textured soil at Kojonup, Western Australia, soil nitrogen accumulated at a fairly steady rate of 42 lb/acre/year over a 5 year period. The increase in soil nitrogen accounted for differences in wheat production following the clover ley whether measured as total dry weight, yield of grain, or uptake of nitrogen. The clover treatments had little effect on the percentage of nitrogen in the grain or on the baking quality of the flour. Each additional year of clover gave an additional yield of 120 lb of wheat grain per acre for the first crop. Yields for second crops were considerably lower than the first but residual effects were evident. A practical implication of the results is that short leys of 1 to 2 years' duration followed by a single cereal crop could be a suitable cropping practice for the Kojonup area.